A transflective display has a reflective mode of operation and a transmissive mode of operation. In the reflective mode the source of illumination for the display is ambient light which is reflected by a reflector. In the transmissive mode, the source of illumination for the display is a back light. A back light may comprise a light source and a light guide, alternatively a distributed light source such as an organic light emitting diode or a thin-film electroluminescent film.